A solder bonding method has widely been used as a method for mounting electronic components on a substrate. Connection electrodes, such as bumps, provided on electronic components are solder-bonded to electrodes on a substrate, thereby establishing electrical conductivity between the electronic components and the substrate. Further, the thus-mounted electronic components are retained on the substrate by means of solder joints. When external force, such as thermal stress stemming from a heat cycle, acts on the electronic components in an operating state after mounting of the components, deficient strength is provided by only the solder joints. For this reason, the electronic components are bonded to the substrate through use of a reinforcement resin and also by means of solder bonding, thereby reinforcing retaining force originating from the solder joints (see; for instance, Patent Document 1).
In an example described in connection with the Patent Document, solder joints are bonded by means of cream solder (solder paste) in a mount surface block in which a semiconductor package whose underside has a plurality of solder joints is mounted on a printed wiring board. Further, some of the solder joints situated along outer edges are locally reinforced by means of reinforcing material including a thermosetting resin. Specifically, in the related art, there have been used two types of bonding materials that differ from each other in terms of a component composition system; namely, flux-containing cream solder used for solder-bonding connection electrodes, such as bumps, to electrodes on a substrate and a reinforcement material for fixing a component body, such as a semiconductor package, to the substrate in a reinforcing manner.